


Aren't You A Little Young to be Building an Interdimensional Portal?

by kittyhazelnut



Category: Phineas and Ferb, Supernatural
Genre: Crossover, Gen, Phineas and Ferb/Supernatural Crossover, PnF, SPN - Freeform
Language: English
Status: Completed
Published: 2020-05-24
Updated: 2020-05-26
Packaged: 2021-03-02 22:48:59
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 15
Words: 16,343
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24354595
Author URL: https://archiveofourown.org/users/kittyhazelnut/pseuds/kittyhazelnut
Summary: Sam and Dean Winchester are just trying to save their mother from an apocalyptic doom. Thanks to Dr. Doofenshmirtz's desperate attempt to make a friend, they get stranded in Danville instead. The hunters enlist the help of a group of children to build a portal home, while OWCA agent Perry the Platypus works with his nemesis to get rid of the threat.
Comments: 27
Kudos: 46





	1. Chapter 1

**Author's Note:**

> Like any episode of Phineas and Ferb, there's a lot going on at the same time, and it tends to overlap. To keep both timelines in check, there are going to be a lot of long chapters and a lot of short chapters.

“Uh, Dean?” Sam gives a nervous chuckle. “I have a feeling we’re not in apocalyptic Kansas anymore.”

Dean scoffs. “Yeah, thanks for the update, Sammy.”

The two men look around, puzzled. They've been to the apocalypse world that their mother is trapped in once before, courtesy of fetus Jack’s interdimensional portal rift. It was not a pretty sight. The land was, unsurprisingly, deserted and war-stricken. The Judeo-Christian apocalypse tends to do that to a place.

This world is disconcerting in a different way. It’s bright and cheerful, and everywhere they look, people are laughing and smiling. This universe isn;t some post-apocalyptic thriller. It’s freaking Maybury 2.0. This definitely is not where they’re going to find Mary, but the rift is already closed. 

“Dude,” Dean says quietly. 

“Yeah?” Sam asks.

“We are so fucked.”


	2. Chapter 2

Five Minutes Earlier…

“Perry the Platypus!” Doofenshmirtz says with a frown. “You’re late! What, you destroy 150 of my inators, and suddenly, I’m not important enough to keep a schedule with?”

Perry chatters apologetically. At least, he looks apologetic. Doofenshmirtz doesn’t really know what he means when he makes that noise. Usually he can use context clues, but sometimes, he just has to make a guess and hope for the best. He’s okay with the language barrier, though. He still likes trying to destroy his nemesis, whether he understands what his little friend says or not.

“Anyways…” Doofenshmirtz begins.

A net scoops Perry up without warning. Doofenshmirtz has used this trapping method a few times, when he couldn’t think of anything thematically related to his current invention. Sure, Perry always escapes eventually, but it holds him for the duration of his emotionally scarring backstory and his introduction of his inator, and that’s the important part.

“You see, Perry the Platypus,” Doofenshmirtz says, “all my life, I’ve just wanted to have a friend, but I was never cool enough. Everyone just laughed at me. Now, I’ve tried to make myself cool -- you know that; you just blew up my cool-inator a few weeks ago. I’ve finally come to realize that I will never fit our world’s definition of ‘cool.’”

Perry chatters sympathetically. 

“And then I heard about the ‘infinite universes’ theory,” Doofenshmirtz continues, “and it hit me! If there’s a universe for everything, then there’s got to be a universe where I’m cool, and everyone from Drusselsteinian isn’t!”

Perry stares at him blankly.

“Now, I can’t just open up a portal into that dimension. That would be too hard,” Doofenshmirtz tells him. “Instead, I’m going to draw every interdimensional portal in the multiverse here, to the tri-state area, using this!” Doofenshmirtz gestures to his new inator sitting on the balcony. “Behold, the dimension-changer-intator!” 

He pauses to give Perry a moment to behold it.

“Now, obviously, I can’t force someone from another dimension to open up a portal right when I fire it, but if there are really infinite universes, someone is bound to be opening a portal from one of them, right? So I’ll just bring them over here, and we can be best friends!”

Perry chatters quietly.

“Oh, I’m sorry, Perry the Platypus,” Doofenshmirtz says with a frown. “It’s not that I don’t like being your nemesis. I do! It’s just that I really want a friend, you know? Not just a secret agent that breaks down my door every day.” 

Perry glances at the platypus-sized hole in the door. 

“But I promise,” Doofenshmirtz continues. “Nothing is going to change between us. I’m not replacing you; I’m just expanding my friendship circle.”

Perry chatters again.

“I’m glad you understand,” Doofenshmirtz says. At least, he hopes Perry understands, but, again, with the language barrier, he’s kind of making assumptions. “Now, watch as I summon a new friend from another dimension!”

Doofenshmirtz walks over to the dimension-changer-inator, but he pauses before he fires it. He’s going to meet whoever is opening a portal when he presses that button. The very instant he presses it will shape the rest of his life. This is a big moment for him. This will determine who his new best friend is. He doesn’t want to push it too soon, but he doesn’t want to wait too long, either. He has faith that when his new best friend is opening a portal, he’ll know.

Without warning, Perry flies from his trap and kicks Doofenshmirtz in the face. This results in a bit of a scuffle and, per usual, Doofenshmirtz ends up lying on the ground as Perry heads for the self destruct button, which Doofenshmirtz expertly hid under the barrel of the inator. 

Perry looks around for a few moments, then points at the big red button that fires the inator. Doofenshmirtz is about to tell him that, but he stops himself just in time. He doesn't need to tell Perry, right? It's not like the game is over just because Doofenshmirtz is on the ground and Perry's not. And OWCA never specifically forbid him from lying to their agents. He’s evil. Isn’t he supposed to lie.

So Doofenshmirtz nods. "Yep, that right there, that's the self destruct button. Go on. Hit it. Hit the self destruct button."

Perry just stares at him. 

"Go on," Doofenshmirtz repeats. "You win. Hit the destruct button."

Perry hesitates, but he hits the button anyway. 

The dimension-changer-inator shoots off a large green ray, and Doofenshmirtz cackles. "Thank you, Perry the Platypus! You've just drawn every single interdimensional portal in the multiverse right into the tri-state area!" 

Perry's eyes widen. 

"Let's go see who my new friends are!" Doofenshmirtz hops to his feet and heads to the inator. 

Perry steps in front of it, holding his arms out as if he could possibly stop Doofenshmirtz from getting any closer. Obviously, he could, given that he's a semi-aquatic, egg-laying mammal of action (what? Doof respect the theme song!), but holding that pose isn't helping him. 

"Relax, Perry the Platypus!" Doofenshmirtz says. "I already have my new friend. You can blow up the inator in a minute. I just want to take a look. I don't know where you ended up shooting it."

Perry hesitates, then steps aside. Doofenshmirtz looks through the telescope that he so conveniently installed on the inator, pointing exactly where the barrel of the inator is. It should show him exactly where his new friend is.

Instead, it showed him two gun-wielding maniacs. 

"I, uh…" Doofenshmirtz chuckles awkwardly. "I don't think they're going to be my new friends."

Puzzled, Perry hops up to look through the telescope for a moment, then hops back, looking worried. 

"I know, right?" Doofenshmirtz agrees. "I mean, this is a kids' show, for crying out loud! You can't bring guns into a kids' show!"

And then, without so much as a chatter, Perry is hang gliding out of Doofenshmirtz Evil Incorporated. He didn’t even let Doofenshmirtz revel in his success. Sure, he accidentally brought guns into a kid’s show, but his inator technically succeeded, and he was really looking forward to bragging about that.

So Doofenshmirtz stands on the overhang of the building and yells, “Curse you, Perry the Platypus!”


	3. Chapter 3

Perry is used to accidentally letting Doofenshmirtz get off one or two misguided shots before taking down his inator. He's just not used to pushing the button with his own hand. Even as he saw the ray shooting out, he knew he wasn't going to forgive himself for this. Either he had just unleashed a horrible person from another dimension in Danville, or he just brought Doofenshmirtz a new friend, and both options involved probably not seeing Doofenshmirtz as often. He would either have to clean up this mess on his own, essentially being reassigned to the universe’s new inhabitants, or he'd have to watch as Doofenshmirtz essentially replaced him. 

That's all Doofenshmirtz really wanted, anyway. He just wants someone to keep him company, and Perry was more than happy to be that someone while he took out all the inators. That's the thing about nemeses: you love to hate them. It’s definitely true with their relationship.

Unfortunately, Perry's an OWCA agent second and a nemesis third, so when he sees two men standing in the middle of the street with guns, he knows they take priority. But then he realizes that this street they're standing on is less than a block away from Phineas and Ferb's giant backyard invention of the day, and while he does place his position at OWCA above his relationship with his nemesis, he cares more about his host family than anyone else on the planet. 

Perry leaves Doofenshmirtz Evil Incorporated without a moment of hesitation. He's determined to get to those two men before they find his host family. Phineas and Ferb's new summer activity is impossible to miss, and Perry doesn't trust  _ anyone  _ hopping through dimensions with a gun, regardless of whether they may have been planning to go and why. 

But when he gets to the street they had been standing on, they're gone. So, as a last-ditch effort, Perry heads home. He'll check on his family first, then get in touch with Major Monogram. He's going to want to hear about this.


	4. Chapter 4

"So, what do we do now?" Dean asks. 

"I don't know," Sam admits. "I, uh…" He glances around at all the seemingly innocent bystanders. "I guess we should put the guns away."

"Good call," Dean agrees, and both men stow their weapons. "Do you think they know back home that we're about as far from apocalypse world as we could get?" 

"I hope so," Sam says. "I don't see us finding our own way out of here, so they’re pretty much our only rescue plan." 

"How did we even get here, anyway?" Dean asks. "Wasn't Kaia supposed to either get us to apocalypse world or 'the bad place'?" 

"I thought so," Sam says. "Maybe that's where she ended up? I don't know."

"You don't think this dimension could have had something to do with it, do you?" Dean asks. "I mean, I don't see Kaia accidentally opening up a portal  _ here  _ for no reason."

"I hope not," Sam says. "I'd like to think this is a good place. Everything seems normal here. In a perfect world, that'll mean no monsters, no magic, no weird —"

"Dude."

Sam raises an eyebrow. "What?"

"Dude!"

"What?" Sam repeats, annoyed. 

Dean forcefully turns him around. "What the hell is that?"

Sam stares straight ahead, his expression blank. Though, perhaps "straight ahead" is a bit of a misdirect. He's staring  _ up _ and straight ahead. Somewhere, not too far from where they're standing, is a giant dome, so that it's probably a plane hazard. There’s no indication as to what it is, but it’s huge and suspicious and doesn’t feel quite right in an otherwise cheerfully normal dimension.

"Should, we, uh…"

"Check it out?" Dean finishes for him. "Probably not."

"Are you sure?" Sam asks skeptically.

"I am  _ absolutely _ sure," Dean says. "But I say we check it out anyway."

~~

The large, suspicious dome they had spotted turns out to be a very interesting lawn decoration. At least, that's all the Winchesters can gather, because the line outside of this stereotypical suburban house’s backyard stretches on for half a block and they can't get a very good look from out front without a bunch of teenagers yelling at them to get in line. 

" Should we get in line?" Sam asks after a few moments of astonished silence. 

"We don't even know what this  _ is _ ," Dean says. "They could be lining up for the slaughter, for all we know."

Sam pauses, thinking, then turns to one of the teenagers in line. "Hey, what are you waiting for?"

Nothing. 

"Hello?"

Silence. 

"Hey!" Sam taps him on the shoulder. 

The kid takes out his earbuds. "Sorry, what was that?"

"What's the line for?" Dean asks, his arms crossed. 

"I don't know."

Sam scoffs. "You don't know what you're waiting in line for?"

The teen shrugs. "Nah. It's gonna be cool, though. Phineas and Ferb are always making cool things."

"What?"

"Get in line," the teenager suggests. "Check it out yourself. Just hope it doesn't mysteriously disappear before you get a chance to check it out."

"Does that happen a lot?" Sam asks. 

"Oh, yeah," he says. "Every day."

"Seriously?" Dean says incredulously. "These people make something every day, and every day it mysteriously disappears?"

The teenager nods. "Pretty much."

Sam and Dean share a look. It's pretty clear what their next move is. 

Sam shrugs. "Let's get in line."


	5. Chapter 5

"Agent P?" Major Monogram's puzzled face appears on the screen. "What are you doing back here?"

Perry just chatters his teeth, too preoccupied with the email he's sending to even look up at his boss. 

"Agent P?" Major Monogram repeats warily. "Is everything okay?"

Perry holds up a finger, gesturing for Monogram to shut up as he finishes his email, then hits the send button very dramatically before looking back up. 

"What's this?" Monogram asks just moments later. "An email?"

Perry waits impatiently for him to read it. 

_ "'30 percent off Hawaiian shi—' _ " Monogram cuts himself off when he sees Perry's annoyed look. This has to be the first time he's ever acknowledged Perry's facial expressions. "Oh, wait, you sent me an email, too. Hang on."

Perry crosses his arms.

"Here we go," Monogram says. He mumbles as he reads it, and it seems to register about halfway through because he exclaims, "Great googly moogly! Doofenshmirtz accidentally brought two guys with guns into our universe?"

Perry nods solemnly. He had purposely not mentioned that technically,  _ he _ was the one to do it, but the guilt is still weighing on him. 

"That's ridiculous!" Monogram declares. "This is a kids' show, for crying out loud!"

Perry rolls his eyes.

Monogram finishes reading, then looks at Perry. "They were near your host family's house?"

Perry nods. 

"And now you can't find them?" 

Perry nods again. 

"Have they interacted with your host family?" Monogram asks. 

Perry shakes his head. They were the first things he checked on. He even waited for Phineas and Ferb to peek out of their weird arena globe thing before heading down to inform Monogram. Candace is on the phone with Stacey, so she's okay, too. And, of course, Linda and Laurence are at some antiques auction downtown, so Perry's not too worried about them. Linda has a knack for staying out of things, anyway. 

"Good,” Monogram says. “We don’t want these men to compromise your cover.” 

Perry nods warily. Only Monogram would make this about his secret identity. Perry wants his family to stay safe, and he will do whatever it takes to accomplish that goal, even if his identity is compromised in the process. Obviously, he’d like to avoid that if possible because he likes to spend time with his family, but if that’s what it comes to...

"Well, sir, they did just build a giant Baseball W-6 stadium in the backyard," Carl remarks. "That could draw some attention."

That’s exactly what Perry was afraid of. He’s not sure if Carl knows this because he keeps tabs on the Flynn-Fletchers or if it’s just because they’re doing something huge again, but he hopes it’s not the latter. If Carl found it by accident, the two dimension-hoppers could, too.

"They built a  _ what _ ?" Monogram asks.

"A Baseball W-6 stadium," Carl repeats. 

"What's Baseball W-6?" 

"Well, sir, it's —"

Perry chatters loudly, cutting them off. He can usually just leave them alone while he sneaks off to do his job, but he needs his instructions. This is well out of his jurisdiction. He needs Monogram to tell him what to do.

"Oh, right, sorry," Monogram says. "Ordinarily, I would tell you to take care of them, but they have guns and we don't have the budget to pay your medical bills."

Perry scowls. What's the point of employee benefits if they don't even work?

"I think your best bet is to work with Doofenshmirtz to send them back," Monogram continues. 

Perry gapes at him. Is he kidding? Doofenshmirtz can barely tie his own shoes. Perry wouldn't trust him with his own life, nevermind the lives of everyone in Danville. 

" _ Now _ , Agent P," Monogram says. "Before anyone gets hurt."

Perry salutes him, then heads for his hovercraft. Well, this is going to be interesting.


	6. Chapter 6

So maybe the kid wasn't lying. 

One moment, the giant dome is standing tall in the backyard. The next moment, it's gone — and not long before Sam and Dean reach the front of the line, which is annoying. There's a collective groan from everyone else waiting in line, and they disperse. 

"Great," Dean mutters. "That's just great."

"Hey, just 'cause the thing's gone doesn't mean we can't talk to them," Sam says. "What did the guy call them? Phineas and Ferb? Maybe they can help."

"What, you think they can  _ build _ an interdimensional portal?" Dean asks skeptically. "That's a bit of a leap to make from a giant dome."

"Well, we don't have much choice, do we?" Sam asks. "It's either ask around or just sit on our asses and hope Jack can open another rift, and call me crazy, but I really don't think Jack knows how to track us through dimensions."

Dean hesitates, then sighs. "Fine. Let's go."

They head to the yard that used to house a giant dome. There's no one waiting out front, so Sam and Dean head to the gate to the backyard instead. This is where the line had been heading, after all. It's probably where they'll find the goods. 

"Ready?" Sam asks, hand on the gate. 

Dean reaches under his flannel, his hand around his gun. "Ready."

Sam pushes the gate open, expecting to see something big and bad. Instead, there's just a group of kids about to head inside. The Winchesters freeze. Is this not Phineas and Ferb's house? Did they mix up the addresses? What's going on?

"What do you want?" one of the kids — a larger boy in a black skull tee shirt — asks them, which is all it takes to get the attention of the other kids. 

"Oh, we, uh…" Dean drops his hand to his side and looks at his brother helplessly. 

"We were looking for someone," Sam says. "But I think we have the wrong house."

"Who are you looking for?" a different boy — smaller, with orange hair and a triangular head — asks. "Maybe we know them."

"Phineas and Ferb?" Sam says, which is honestly more of a question than an answer. 

"Oh, that's us!" he says with a grin. "I'm Phineas. That's my brother, Ferb." He gestures to a taller boy with green hair. "Why do you ask?"

"Woah, hang on," Dean says. " _ You two _ built that giant dome thing?" 

"Well, not  _ just _ us," Phineas says. "Isabella, Buford, and Baljeet helped, too."

"And, let me guess," Dean deadpans. "Those are the other kids standing right next to you."

Phineas nods. 

"Uh huh…" Dean looks at Sam, who's just as unsure as to how to proceed from here. 

"What do you need?" Phineas asks. "If you're looking for the Baseball W-6 game, it already disappeared."

"The  _ what _ ?" Sam asks. 

"Baseball W-6," Phineas repeats. "You know, the most extreme hypothetical way to play? Like Football X-7 and Hockey Z-9."

"Right, right," Dean mutters. "Um… okay, I think we have the wrong house."

"Are you sure?" Phineas asks. "There's no other Phineas  _ or _ Ferb in the tri-state area."

"Yeah, no, I'm pretty sure," Dean says. "Thanks."

"Kids?" a woman calls from inside the house. "Are you coming? Don't want Candace to eat all the pie on you!"

"In a minute!" Phineas calls back. He turns back to Sam and Dean to ask, "Do you guys want some pie?"

"Yes!" Dean says immediately.

"No, I think we're good," Sam says, shooting Dean a look. "I still think this is the wrong house."

"Sam!" Dean whines. 

"If you're not in a hurry, you could come get pie anyway," the only girl of the group — who, judging by the list of names, must be Isabella — suggests. "I could get my hospitality badge!"

"Your what?" Sam asks, staring at her blankly. 

"My hospitality badge," she repeats. "I'm a Fireside Girl.”

“You’re a  _ what _ ?” Dean asks.

“You don’t know what the Fireside Girls are?” Isabella asks, dumbfounded.

“Um…” Dean looks at his brother helplessly, but Sam just shrugs. He’s decently sure Fireside Girls don’t exist in their universe, though it sounds like it might be this universe’s Girl Scouts.

“You’re not from around here, are you?” Ferb asks in a voice that’s far lower and more British than either Winchester was expecting.

“Uh, no, not quite,” Sam says with a nervous chuckle.

“Oh, where are you from?” Phineas asks, sounding genuinely interested. He seems like a nice kid. This is probably what Jack would have been like, had he not skipped over his elementary school years.

“Not here,” Dean says. 

“Are you aliens?” the big kid asks eagerly.

“What? No!” Sam says immediately.

“Buford, not everyone we meet is going to be an alien,” Isabella scolds him. 

Dean chuckles. “You say that like you meet a lot of aliens.”

“Well, not a lot, but we did help our friend Meep stop an evil alien from taking over their world by harnessing the power of cuteness,” Phineas says.

“Really, now?” Dean bites back a laugh. “And how did you do that?”

“Isabella defeated him with her own cuteness,” Phineas says matter-of-factly.

Sam and Dean both look at Isabella, who beams.

“You guys have quite the imagination, I will give you that,” Sam says. 

“No, we really did,” Phineas says. “We still hear from Meep every now and then.”

“Uh huh,” Dean says, amused. “And how’d you guys meet? Did you build an alien tracking signal?”

Sam shoots him a glare. If these kids want to pretend they saved an alien race, they can pretend they saved an alien race. They’re, like, eight, for god’s sake.

“No, he crash landed in our yard,” Phineas says. “We accidentally hit his spaceship with the remote control baseball we made.”

“Right, of course,” Dean says. 

“I mean, they  _ did _ just built a giant baseball stadium,” Sam reminds him before asking Phineas, "So you guys just, like… build things? All the time?"

Phineas nods. "We build something every day."

"What's the weirdest, least believable thing you've ever built?" Sam asks. 

"Dude!" Dean hisses, smacking him on the shoulder. Sam just smacks him back. There’s a method to his madness.

"I don't know," Phineas says. He looks over at his friends. "What do you guys think?"

"Definitely when you built a haunted house to get rid of my hiccups," Isabella says. 

"Does fighting the evil pharmacists count?" the other boy — who, by process of elimination, must be Baljeet — says. 

"Or the giant platypus catapults," Buford adds. 

"Oh, speaking of which, where's Perry?" Isabella asks. "He's usually back by now."

Phineas looks around. "Huh. That's a good question." He looks at Ferb, who just shrugs. "Weird."

"Who's Perry?" Dean asks. 

"He's our pet platypus," Phineas says. "He usually waddles away and comes back by snack time."

"I'm sorry, you have a  _ pet platypus _ ?" Dean repeats, gaping at him. 

Phineas nods. "He doesn't do much, though."

"Why do you have a pet platypus?" Dean asks, dumbfounded.

"Why not?" Phineas asks.

Putting them back on task, Sam asks, "So you guys don't do the impossible. There's no magic."

"Santa used our rest stop once," Phineas says. "Does that count as magic?"

"What does that even mean?" Dean asks. 

Phineas explains the plot to the entire Christmas episode. They built a giant rest stop for Santa Claus to thank him for delivering gifts every year. Then the entire tri-state area was inexplicably deemed naughty — totally not because of an evil scientist — which meant that not only was Santa not coming and thus would not see the rest stop, but also that no one in Danville would get gifts. So, as any normal group of children would do in this situation, they amplified the reach of the local Danville station and aired a brief segment about this to the North Pole. 

A couple elves came down to Danville, and they told Phineas and his friends that the whole city seemed to be naughty, not the people themselves. Though the naught signal cleared up, it was too late for Santa to bring them gifts, so Phineas and Ferb built a sleigh and delivered presents that the elves whipped up. They later found Santa in the rest stop, where he basically admitted to setting the whole thing up so that everyone would get their wish. 

"Well, that sure is a story," Dean says, rolling his eyes. "Yeah, Sam, I think we should go."

"Wait, hold on," Sam says quickly. "Phineas, you can make  _ anything _ ?" 

"I guess so," Phineas says. "Why?"

"Could you make an interdimensional portal?" Sam asks. 

"Dude!" Dean smacks him in the arm in a failed attempt to shut him up. 

"Uh…" Phineas looks at his friends, and everyone just shrugs. 

"Are you seriously asking a bunch of  _ children _ to get us home?" Dean hisses. 

"Maybe that's just how this universe is," Sam says.

"You're from a different universe?" Isabella repeats. 

"Yeah, pretty much," Sam says. "We were trying to go to a  _ different _ different universe, but we somehow ended up here and we don't really have an escape plan."

"I guess we can try to get you home," Phineas says. He looks at his brother. "Ferb?"

Ferb produces a large and shocking detailed blueprint from seemingly nowhere. 

"Thanks, Ferb."

Ferb just gives him finger guns.


	7. Chapter 7

Perry knocks on Doofenshmirtz's door this time. He doesn't mind destroying the place during their daily battles, but he'd feel bad if he broke in every time he showed up. He may technically still be on the clock — though he can already guess he's not getting any overtime for this, given OWCA's inability to manage their funding — but he still has manners. 

"Just a minute!" Doofenshmirtz calls out. 

Perry taps his foot impatiently. 

There's a loud clamour inside, and Perry braces for the worst. To say he's surprised to see Doofenshmirtz open the door and look fairly normal is an understatement, to say the least. His lab coat has a little dark purple paint on it, but otherwise, he looks fine. No bumps and bruises from whatever that clatter was, and no embarrassing lounge clothes. Perry’s not sure which one is more surprising.

"Perry the Platypus?" Doofenshmirtz says, surprised. "What are you doing back here? I haven't even done anything evil yet!"

Perry pushes past him and into his penthouse. The first thing he notices is the platypus-sized hole in the wall, which it looks like Doofenshmirtz has been boarding up. That explains the paint. He's just trying to fix the place up. Perry had always assumed he hired someone to do that. Apparently, Charlene’s alimony checks only get him so far.

"Perry the Platypus?" Doofenshmirtz says warily. "Are you okay?"

Perry takes off his watch and hands it to the evil scientist. Monogram explains — via a pre-recorded message — that Perry has returned to help Doofenshmirtz get rid of the intruders. 

But instead of watching, Doofenshmirtz says a surprised, "You wear a watch?" 

Perry rolls his eyes and gives an annoyed chatter.

"How have I never noticed that before?" Doofenshmirtz asks. "I swear, I see you here every day, and you never have a watch on!"

Perry chatters again. 

"Why did you give me your watch, anyway?" Doofenshmirtz asks. "It's not going to fit me."

_ "Self destruct will initiate in three… two… _ "

Perry jumps up and kicks the watch out of Doofenshmirtz's hand just before it explodes. This is exactly what Perry was talking about. OWCA would rather build a bunch of weird secret entrances to lairs and self destructible tools than pay their employees fairly. If Perry didn't like thwarting Doofenshmirtz so much, he probably would have quit long ago. 

"I don't get it," Doofenshmirtz says. "Why would you give me a watch that was about to explode? Was that a trap? I don't…?"

Perry rolls his eyes and heads to the broken portal-changer-inator. He gestures to it, then to the spot it hit. 

"You want me to fire the inator again?" Doofenshmirtz guesses. "I never thought you'd ask!"

Perry shakes his head quickly. He gestures to the inator, then makes a circle with his hand that he hopes looks like "undo it."

"You want me to spin the inator?" Doofenshmirtz guesses. 

Perry shakes his head again. He points at the inator, then to the spot that the two men appeared in. Then he mimes cutting his throat with his thumb. 

"You want me to kill the street with the inator?" Doofenshmirtz tries again. 

Perry rolls his eyes. He looks around, then makes his way to a different busted up inator. He points to the portal-changer-inator, then to the other inator's reverse switch. 

"You want me to combine the portal-changer-inator with the giant ice cream machine?" Doofenshmirtz asks. 

Perry pulls the reverse switch off the ice cream machine — he's decently sure the blueprint Phineas and Ferb ordered that Doofenshmirtz accidentally used did not have a reverse switch, and yet here they are — and holds it up in front of the portal-changer-inator, where he flicks the switch to reverse again. 

"You want me to put a reverse switch on the portal-changer-inator?" Doofenshmirtz says, confused. 

Perry nods. 

"Wouldn’t the reverse of an inator that makes all portals go to Danville just make all portals go away from Danville?" Doofenshmirtz asks. "I don't know what that's going to accomplish."

Perry just stares at him for a very long few moments. 

"Oh!" Doofenshmirtz exclaims. "You want it to make the portal so you can go to another dimension!"

Perry smacks his head with the palm of his hand. 

"Still no?" Doofenshmirtz guesses. 

Perry just shakes his head. 

"Okay, okay…" Doofenshmirtz thinks about this for a minute. Very slowly, he says, "You… want me to reverse… the portal-changer-inator… because there's an outside…"

Perry sighs and sits down on the floor. This might take a while. 

"Because there are  _ people _ outside," Doofenshmirtz tries again, which is when it seems to occur to him, because he gets excited. "Because there are people from another dimension outside! You want me to send them back!" 

Perry nods enthusiastically. 

"Yeah, I can't do that."

Perry stares at him. 

"I told you! The reverse switch would just send all portals  _ away _ from Danville!" Doofenshmirtz says. "I'd have to build a whole new inator if _ I _ wanted to open the portal."

Perry nods. God, his life would be so much easier if he could just talk to the guy. Doofenshmirtz isn't very good at charades. 

"You want me to build a new inator?" Doofenshmirtz says, shocked. "You never want me to build inators!"

Perry nods again. He’d like to think Doofenshmirtz knows that this is a one-time thing because of extenuating circumstances, but they’ll cross that bridge when they come to it. He just wants these invaders gone. 

"I think I already have the blueprint, too!" Doofenshmirtz says, beaming. He walks over to the door to what Perry assumes is a closet. "It's somewhere in here!" 

Doofenshmirtz opens the door to reveal boxes and boxes of blueprints. Perry gapes at them, awestruck. He thought Doofenshmirtz had made a lot of inators in the past, but that's nothing compared to all the ones he's  _ thought  _ of making. There have to be  _ thousands  _ of blueprints in here. 

"So, uh…" Doofenshmirtz rubs the back of his neck and gives an awkward chuckle. "How are we going to do this?"

Perry just heads to the box closest to the door and starts to dig through it. This is going to take a while.


	8. Chapter 8

Phineas and Ferb get right to work. They manage to find everything they're going to need just by calling in a favor. Not only that, but they gather all their permits, meaning that everything they're doing is completely legal. And, perhaps most shockingly of all, this all seems easy to them. 

"This is weird, right?" Dean asks his brother quietly. "It's not just me?"

"No, this is definitely weird," Sam agrees, his voice just as low. "But I guess in this dimension, kids can be expert inventors and no one bats an eye."

"I didn't think it was possible to open a portal scientifically," Dean says. "I thought it was a magic-only type deal."

"Anything's possible when Phineas decides to do it!" Isabella says cheerfully. 

Sam and Dean both jump. How long has she been listening for? 

"Does he really do this every day?" Sam asks. 

"Oh, yeah," Buford says. "Every day this summer — which feels like a lot more than one summer."

"It does, doesn't it?" Isabella agrees. 

Sam and Dean share a look, but neither of them knows what to say to that. God, this is a weird universe.

“Isn't he a little young to be building an interdimensional portal?” Dean asks.

“Yes, yes he is,” she replies.

That’s not what Sam’s worried about, though. He knows that people age differently. At eight years old, Sam was taking middle school math classes. At eight yeras old, Dean was hunting monsters. If these eight-year-olds can build like an adult, they can build like an adult. Sam just wants to make sure it’s safe, so he asks, "Has anything he's made ever not worked?" 

"No, it always works," Buford says. "It just doesn't usually stick around for long."

"Right, someone mentioned that earlier,” Dean says. “How does that even happen?” 

"No one knows,” Baljeet says. “It always disappears right before Candace brings their mom out.”

"Who's Candace?" Sam and Dean ask in unison. 

As if on cue, a young girl steps out of the house and demands, "What do you think you're doing?" as she glares at Phineas and Ferb.

" _ That's _ Candace," Isabella says. 

"She's Phineas and Ferb's sister," Baljeet adds, in case there was any confusion. 

"What's her deal?" Dean asks. 

"No one knows," Buford says. 

"She's been trying to 'bust' Phineas and Ferb all summer," Baljeet explains. "But, again, everything always disappears right before Mrs. Flynn-Fletcher can see it."

"So their parents have no idea what they're doing?" Sam asks, gaping at him. That's so incredibly unsafe, not to mention how  _ expensive _ this must be. 

"Their dad does," Isabella says. "I don't think their mom does, though."

"And their dad is okay with this?" Dean scoffs. "Our dad would have killed us if we did anything like this!"

"I'm telling Mom!" Candace practically screeches, running back inside. 

"So, what, everything's going to disappear now?" Dean asks skeptically. 

"What 'everything'?" Buford asks. "They haven't even started."

"The blueprint, for one," Sam says. 

"She won't think anything of it," Isabella says. "This has a funny way of working out."

Candace returns to the backyard, dragging and a woman who must be her mother. The girl points at Phineas and Ferb, who both had been looking at the blueprint until they appeared. "See?"

"Oh, what are you guys doing?" their mother asks, like she thinks this is cute. 

"We're building an interdimensional portal to help Sam and Dean get back to their world," Phineas says matter-of-factly.

"Really?" she says, amused. "And who are Sam and Dean?"

"They're over there," Phineas says, and Ferb points at them. 

She seems taken aback when she sees them. "Hello?"

"Hi," Sam says with a kind smile. He walks up to her and shakes her hand. "I'm Sam, and that's my brother, Dean. We're new to the area and we just happened to run into your sons, and our son was just here playing baseball with them not too long ago, so we just wanted to meet his new friends."

"I didn't realize we had new neighbors," she says, but she doesn't seem to find that suspicious at all. "What's your son's name?"

"Jack," Sam and Dean say in unison. 

"Well, I can't wait to meet him," she says. "Do you want to come inside?"

"Oh, no, I think we're going to get going on a minute," Sam lies. 

"It was nice to meet you," she says. "I'm Linda. Feel free to stop by any time."

And then she's back in the house, like nothing even happened.

Candace groans, exasperated, then looks at her two brothers to say a firm, "I will be back," before storming into the house. 

"I don't get it," Phineas says to the Winchesters. "Why would you lie?"

"Because I don't think your mom is going to let you build an interdimensional portal in the backyard," Dean says.

"And she's definitely not going to believe that we're from another dimension," Sam adds. 

"I don't think she'd care," Phineas says. 

Sam and Dean look at his friends, not quite sure what to make of this reaction in light of what they said, and the kids just shake their heads, so the two men drop the subject. 

"Do you really have a son?" Baljeet asks.

Dean says, "No," at the same time that Sam says, "Yes," so the younger Winchester elaborates, "There's this kid we're supposed to be looking after, but he's not  _ technically _ our son."

"He doesn't have to share your DNA to be your son," Phineas says. "Ferb and I don't share  _ any _ DNA, and we're still brothers."

"Wow." Dean chuckles. "It's the 'family don't end in blood' squad."

"I like that," Phineas says. 

Someone honks their horn from out front. 

"Oh, those are the parts!" Phineas says, running out of the yard. Ferb follows him out. 

"So, how long do you think this is going to take?" Dean asks. 

"Only about the length of a montage," Isabella says. 

Sam and Dean share a look, but there's not much you can say to that. This is a weird universe.


	9. Chapter 9

After what has to be at least half an hour of digging through blueprints, all the names start to blur together. There comes a point where Perry isn't even sure the blueprints he's skimming through aren't the ones he's looking for. He almost doesn't notice that he's looking at the "Dimensional-portal-inator" blueprints until he's about to toss it away. Fortunately, he catches himself just in time.

Perry grabs the blueprint and runs up to Doofenshmirtz. He shoves it in the scientist's face to get his attention.

"What's this?" Doofenshmirtz takes the blueprint and looks it over. "Oh, no, Perry the Platypus, this is a dimensional-portal-inator, not the  _ inter _ dimensional-portal-inator. Totally different things."

Perry stares at him blankly. 

"Well, you see," Doofenshmirtz says, "the  _ inter _ dimensional-portal-inator lets you portal between dimensions. The dimension-portal-inator lets you portal to other places in your dimension."

Perry stares at him. 

"It's kind of like teleportation, but with portals," Doofenshmirtz adds. 

Perry continues staring at him for another few moments, then takes the blueprint back from Doofenshmirtz and throws it out of the blueprint closet.

"You better clean that up before you leave," Doofenshmirtz says. "I'm your nemesis, Perry the Platypus, not your maid."

Perry rolls his eyes and heads back to his box of blueprints. This is going to take a long time.

It's a few minutes later when Vanessa comes home, announcing herself with a loud, "Dad?"

"Oh, Vanessa!" Doofenshmirtz says with a grin, running out of the closet to see her. 

"Dad? What are you doing in there?" she asks, confused. 

"Perry the Platypus and I are looking for my interdimensional-portal-inator," Doofenshmirtz says. 

"Perry's here?" 

Perry pokes his head out of the closet and waves. 

"Oh, hi, Perry," she says, before it really seems to register with her. She looks back at her father and asks, "Why is Perry still here? Hasn't he usually thwarted you by now? And why is he  _ helping _ you?" She gasps. "You turned him evil again, didn't you!"

Perry shakes his head. Doofenshmirtz never tries the same scheme twice. Turning Perry into his evil servant failed once, so he's safe from that now. 

"No, not this time," Doofenshmirtz says. "We're trying to send some people back to the dimension they came from so they don't take over the tri-state area before I get the chance to."

Perry shoots him a glare. That is  _ not _ what's happening.

"Well, good luck with that," Vanessa says. 

Perry goes back to searching through blueprints, and, not long after, Doofenshmirtz joins him, and it's like Vanessa never showed up. 

~~

It has to be an hour later, and Perry is exhausted. Usually, by now, he'd be sleeping in his little platypus bed by the kitchen table. He’s never stayed at Doofenshmirtz’s house for this long before, and he's not sure how much longer he can do this. 

Vanessa pokes her head in. "You're still at this?"

Perry chatters quietly.

Doofenshmirtz shrugs. "I have a lot of blueprints."

"Why don't you just get a new one?" Vanessa asks. 

"They don't sell the interdimensional-portal-inator blueprints anymore," Doofenshmirtz says. "That's why I had to get it a few months ago."

"Is that what all these blueprints are?" Vanessa asks. "Discontinued ones you grabbed before they stopped selling them?"

"A lot of them, yeah," Doofenshmirtz says. "And there's a few boxes of blueprints I've already used over there." He points to the corner of the room. 

"You're not going to stop until you find this blueprint, are you?" Vanessa asks. 

"Nope," Doofenshmirtz says cheerfully, and Perry gives a small, tired chatter. 

Vanessa sighs. "Do you want help?"

Perry nods quickly. He would  _ love _ help. 

"What's this?" Doofenshmirtz gasps. "You're taking an interest in the family business!"

"It's not the family business if you're the only one in the family doing it," Vanessa remarks. 

"But I'm not the only one, because you're doing it, too!" Doofenshmirtz says, beaming. 

"I'm only helping because I feel bad that Perry's stuck here," Vanessa says. 

"Oh, don't worry about him," Doofenshmirtz says. "I'm sure he's getting overtime for this."

Perry shakes his head. 

"What?" Doofenshmirtz scoffs. "When this is over, I'm going to have a serious talk with Francis about this."

Perry rolls his eyes. Monogram would never listen to him. It's nice that Doofenshmirtz cares, though. He's cool that way.

Vanessa sits down next to Perry. "Have you looked through this box yet?"

Perry shakes his head. 

Vanessa sighs and pulls the box over to her. "This is going to be fun."

~~

Snow-inator.

_ Nope _ .

Grow-inator.

_ Nope _ .

Show-inator.

_ Nope _ .

If Perry wasn't so worried about these guys with guns, he would really consider ignoring Monogram's orders and just heading home. He thought Doofenshmirtz made a lot of dumb inators, but the ones he hasn't made are so much worse. He doesn’t even know what half of these ones do.

Hand-to-foot-inator.

_ Nope _ .

Dust-devil-inator.

_ Nope _ .

Platypus-translator-inator.

_ Nope _ .

Wait. 

Perry looks at the blueprint for a moment. A platypus-translator-inator? What does Doofenshmirtz want with this? 

"Did you find it?" Vanessa asks, which gets Doofenshmirtz's attention, too. 

Perry shakes his head and rolls the blueprint back up. 

"Well, you definitely found  _ something _ ," Vanessa says. She takes the blueprint from Perry's hands and unrolls it. When she sees what it is, she laughs. "I almost forgot about that!"

"What is it?" Doofenshmirtz asks. 

Vanessa tosses him the blueprint. Doofenshmirtz almost catches it, but he fumbles and it falls to the floor. He picks it up and looks it over. "I don't remember this."

"You don't?" Vanessa says, surprised. "You just got it a few weeks ago. You were talking about how weird it is that you tell Perry everything about yourself, but he can't tell you anything about himself. Remember?"

"Are you sure?" Doofenshmirtz asks. "I think I would remember that."

"You really don't remember? You were going to ask Perry if that was something he would be interested in next time he showed up," Vanessa says. 

"No, I really don't remember," Doofenshmirtz says. "Perry the Platypus, do you remember that?"

Perry shakes his head. He doesn't doubt that it's true, though. This is definitely something Doofenshmirtz would do. He has to admit, it's kind of sweet. He's pretty sure Doofenshmirtz is the only evil scientist that would actually want to hear his nemesis's backstory. 

"I might as well ask now, though," Doofenshmirtz says. "Perry the Platypus, do you want me to make a platypus-translator-inator?" 

Perry hesitates. On one hand, he would love to finally get the chance to talk to Doofenshmirtz. He really does feel like he knows the guy's entire life story, and Perry hasn't been able to tell him anything. Sometimes, he just wants to tell his nemesis that he understands or that he's sorry or that there are about a million better ways to solve the problem he decided to create a complex inator for. 

At the same time, though, if Perry could talk, Doofenshmirtz would never stop asking questions, and there are a lot of things that Perry contractually can't tell him. He can't talk about OWCA. He can't talk about where he came from. He can't talk about the Flynn-Fletchers. Hell, he's pretty sure it hasn't even occurred to Doofenshmirtz that he has a host family, and if it keeps them safe, Perry would like to keep it that way.

It's like when Phineas and Ferb made a whole contraption that allowed them to communicate with animals, just so they could talk to Perry. It was a nice thought. There's a lot Perry would like to tell them. Heck, Perry would be satisfied just to be able to tell them that he loves them. But not only does his contract with OWCA forbid communicating with his host family, but pretending to be a mindless platypus keeps them safe, too. Having a double life means keeping those two lives separate. 

So Perry just shakes his head. He'll have to pass on the translating helmet. Maybe one day, if Perry ever leaves OWCA or Doofenshmirtz ever decides to stop being evil, they can give it a go, but not while it would endanger OWCA and his family. 

"All right, well, if you ever change your mind, you know where to find me," Doofenshmirtz says. "Can you imagine the look on Francis's face if you just went up to him and said hi? No context or anything?"

Perry laughs quietly. He hadn't even thought about that. There's nothing in the OWCA rules that says he can't talk to Major Monogram. It's not like they were expecting their agents to suddenly be able to talk. Perry would scare the heck out of him with that inator.

"I really don't understand how I forgot about that, though," Doofenshmirtz says. 

"I don't, either," Vanessa says. "You were going to ask him after you showed him the amnesia-inator."

"No, I think I'd remember making an amnesia-inator," Doofenshmirtz says. 

Wait. 

The amnesia-inator.

Perry runs over to the used inator boxes. How did it take him this long to figure it out? It was so obvious in hindsight. He could have found this ages ago.

"No, Perry the Platypus, those are the ones I've already made," Doofenshmirtz says. "I don't even know why I keep them around."

Perry digs through the first box, tossing every blueprint he doesn't need behind him. If it's not in this box, it's in another used inator box. He knows that much. 

"Why are you throwing them at me?" Doofenshmirtz asks. 

Perry finally finds it. It has a different name, but it doesn't take much of a stretch of the imagination to think Doofenshmirtz might have gotten the name wrong. It's the other-dimension-inator. He's used this one before. He just doesn't remember. No one remembers. Monogram wiped everyone's memories of that adventure, hiding out in an alternate universe where Doofenshmirtz succeeds in taking over the tri-state area.

Perry hesitates. This didn't go very well last time they used this blueprint. He's not sure he wants to go at it again. But he can't just leave these guys with guns to wander around Danville, either, so he doesn't have much of a choice. He tosses Doofenshmirtz the blueprint. 

"Oh, you found it!" Doofenshmirtz says, beaming. "Hey, how'd you know it was in there?"

Perry just shrugs. He wouldn't get into the details even if he could. They erased Doofenshmirtz’s mind with the kids’ for a reason. Doofenshmirtz doesn’t learn from his mistakes. He would just try opening a portal into another dimension for kicks again, and that probably won’t end much better than it did last time.


	10. Chapter 10

"Do you want help with anything?" Dean asks, watching as Phineas and Ferb build their machine effortlessly. 

"No, we're good," Phineas says. 

"Are you sure?" Dean asks. "'Cause I'm pretty good with building, too." He built an EMF meter out of a Walkman, for god's sake. He can definitely help them build an interdimensional portal with a blueprint right in front of them. 

"Yeah, we're fine," Phineas says. 

"Okay…" Dean frowns. This really looks like it would have been fun. Obviously, his first priority is getting home so he can try to find his mom, but still. If someone's going to build an interdimensional portal right in front of him, he'd like to get in on the action. 

"You know," Isabella says to him, "you can drop as many hints that you want to work on this with him as you'd like, but he's not going to figure it out."

"What?"

"He's the smartest person I know, but he can be really dumb," Isabella says. "I'm just sayin'."

"Duly noted," Dean says. 

"Uh, guys?" Phineas says warily. "Is there another transistor lying around somewhere?"

"Why?" Sam asks. "Didn't you already put one in?"

"It's not the one we ordered," Phineas says. "We'd blow the power in all of Danville — maybe in all of the tri-state area."

"So order a new one," Dean says. 

"I will," Phineas says. "I was just hoping it was already lying around here."

"I don't think so," Isabella says. 

"That's okay. I'll just get a new one." Phineas pulls out a cell phone — why do kids need cell phones at that age? — and explains that his part somehow got switched with a different transistor. 

"So close, yet so far," Dean mutters, and Sam nods in agreement. 

"What do you mean, you don't have it?" Phineas asks. 

"Emphasis on the 'so far,'" Dean says. 

"Someone else bought this exact transistor three minutes ago?" Phineas says, dumbfounded. "Okay, are you getting more in soon?" 

There's a pause, as whoever's on the other end of the call speaks. 

"You just sold your last transistor, and you're not getting any more?" Phineas says. 

There's another pause. 

"So someone else is trying to make an interdimensional portal?" Phineas asks. "That's… weird."

"I hope that someone's having better luck than we are," Dean mutters. 

"Okay, thank you," Phineas says before hanging up. "I'm sorry, guys. It looks like we're out of luck."

Sam sighs. "Well, thank you for trying."

And they're back to square one.


	11. Chapter 11

Perry and Vanessa watch as Doofenshmirtz goes through his old and broken inators, trying to find the parts he'll need for the other-dimension-inator. In his words, he doesn't have the budget to make more than one inator in a day, so he has to recycle these.

"Hey, Perry?" Vanessa says. 

Perry looks up at her and chatters. 

"It's getting late," she says. "No one's going to go looking for you, are they? Monogram or someone?"

Perry freezes. It  _ is _ getting late, isn't it? He should have been home ages ago. Last time Phineas and Ferb thought he ran away, they broadcasted an entire musical performance over the whole tri-state area begging him to come home. Even Candace sang a verse, and that's the only nice thing she's ever done for him. Clearly, they're not  _ that _ worried yet, but they have to be wondering where he is. 

Perry pulls out some binoculars from under his fedora — he has  _ everything _ under his fedora _ — _ and looks out on the city from the building's overhang. He just wants to make sure Phineas and Ferb aren't worrying yet. 

But when he peers into the Flynn-Fletcher backyard, he sees the two men with guns talking to the kids and their friends. 

Perry tosses the binoculars to the ground and jumps out of the building without a second thought, hang gliding back home. This is not happening. He's not going to let it happen. 

"Perry?" Vanessa calls after him. 

"Perry the Platypus?" Doofenshmirtz yells. "Where are you going?"

Obviously, Perry can't answer, given that he's a platypus and that he's nowhere near them anymore, but even if he could, the Doofenshmirtz family isn't his top priority anymore. His own family is. 

He lands in the driveway of the Flynn-Fletcher house, and he's faced with a choice. He could either go in the yard and get a look at the scene, or he could try to lure the two gun owners out and hope for the best. The latter could go wrong for obvious reasons, but he's not sure he wants to be stuck in his mindless pet mode around these guys, so he doesn't want to head in, either. 

Stuck between two very bad choices, he opts to go with the method that will choose for him. He makes as much noise as he can in the driveway, smacking things with his tail and chasing away chipmunks, so that someone will come out and check on it. 

"What's that?" an unfamiliar voice asks. He must be one of the dimension changers.

"I don't know," Phineas says warily. "I'm gonna go check it out."

So he's going with the "scope out the area and get stuck in mindless pet mode" strategy. Good to know. He quickly takes his fedora off and falls on all fours.

"I think this is more our speed," the unfamiliar voice says. "Hang on."

Perry stands back up and puts his fedora back on. He's ready for this. And, if he's not ready for this, he's standing right next to his host family's house, so the Flynn-Fletchers can pay the medical bills that OWCA can't afford. 

A man turns the corner, and the first thing Perry notices is that he's tall. Like, really tall. Doofenshmirtz-if-he-stopped-slouching tall. The second thing Perry notices is that not only is he not holding a gun, but he's not reaching for a gun, either. Maybe the Flynn-Fletchers don't need to worry about paying his medical bills. 

"Is this a normal thing in this dimension?" the man mutters to himself. "Beaver-ducks in fedoras?"

Perry jumps up and kicks the man in the face. 

"Ow!" the man yells, smashing into the side of the house. "What kind of beaver-duck are you?"

Perry grabs the man by the ankle and pulls it out from under him, taking him to the ground. He hops up on the man, running along his body and up to his face, ready to take him out, when…

"Dean?"

Perry hops off him, hides his fedora, and falls back on all fours right before Phineas finds him. 

"Oh, Perry, there you are!" Phineas says with a grin. He runs over, picks him up, and gives him a hug. "It was getting late. Ferb and I were starting to worry."

Perry chatters at him. It obviously looks like he's saying nothing — that's his job, after all — but it's an "I love you" chatter. Phineas knows that. Perry has faith in it. 

The man Perry just hit — Dean, it would seem — sits up. It takes him a moment to readjust, but when he does, he gasps. "Phineas, put that thing down!"

"What thing?" Phineas asks. "Perry?"

"What?"

"Perry," he repeats. "He's our platypus. He doesn't do much."

"That's your platypus?" Dean repeats. "Aren't platypi brown?"

Phineas just shrugs.

"Well, your platypus just kicked me in the face," Dean says as he pushes himself to his feet.

"What? He wouldn't do that!" Phineas says. "He's just a platypus. I told you, he doesn't do much."

Perry chatters mindlessly. 

"He did!" Dean insists. "He kicked me in the face!"

"Perry wouldn't hurt a fly," Phineas says. "Come on, Perry. Ferb and I are trying to modify a transistor."

Modify a transistor? What does that even mean? 

Perry lets Phineas carry him back to the backyard, where Ferb is working on something with a blow torch. Basically, Perry gathers, they're doing the impossible again. That's nothing new — though two things in one day is a  _ little _ new. That usually only happens in special episodes. It's weird, though, because the only ones here are the boys and the dimension changers. All their friends are gone.

Phineas puts Perry down under the tree. "Hang on, buddy. We're just trying to help these two get home. Then we can go in for dinner."

It's a good thing that Perry's not supposed to react to anything, because he wouldn't know how to react to this. They're trying to help these two? Don't they understand? They're not aliens from a world ruled by cuteness. They're bad people —  _ genuinely  _ bad people, not like the "evil scientists" of L.O.V.E.M.U.F.F.I.N or “evil aliens” like Mitch. These kids could get hurt. They could get  _ killed _ . 

"Woah, dude," the other dimension traveler says, eyeing his friend with an amused smile. "What happened to you?"

"The platypus happened to me," Dean growls. 

They both look at him, and Perry chatters.

" _ That's _ a platypus?" the other man says uncertainly. 

"Yes, yes he is," Phineas replies. 

"Aren't platypuses brown?" he asks. 

Dean chuckles. "'Platypuses.'"

"What?"

"It's 'platypi,' Sam," Dean says. "Not ‘platypuses.’"

"No, it's 'platypuses,'" Sam says. "'Platypi' is a common misconception."

"Okay, jury?" Dean looks at Phineas, Ferb, and their friends. "What's the verdict?"

"They're both right," Phineas says.

"Though, technically," Ferb says, "'platypi' is derived from Latin grammar, and 'platypus' itself is derived from the Greek roots 'platus' and 'pous,' so the plural would be 'platypodes,' not 'platypi.' 'Platypuses' would be more correct."

Sam and Dean stare at him blankly, but Perry feels a pang of pride. These kids really know their platypus origins, don't they? He can always count on Ferb.

And Ferb can always count on him, both as a snuggle buddy at night and a protector during the day. Perry waddles over to Dean, looking anywhere but him so he doesn't see it coming. 

"Get that thing away from me," Dean says, shoving Sam in front of him. 

"Dude, it's a platypus," Sam says, amused. "Look at his eyes. I doubt he could see you if you were standing right in front of him."

"He can," Ferb says simply. 

"But he won't hurt you," Phineas adds. "Again, he's just a platypus. He doesn't do much."

To prove this, Perry walks in a circle a few times, then lies down in the grass. Oh, this is nice. How he wouldn't like to just close his eyes and fall asleep until Phineas and Ferb bring him inside…

Wait 

He isn't here for a nap. 

Perry stands back up and walks towards the dimension changers. 

"Seriously, get that thing away from me," Dean says. "I don't care if  _ you guys _ think he's harmless. He's not."

Perry just stands there. 

"Dean,  _ relax _ ," Sam says. He crouches down and holds a hand out. "Hey, buddy."

Perry changes course, from Dean to Sam. He'll take what he can get. He stops right in front of the man, enjoying the petting he gets in spite of himself.

"See?" Sam says. "Harmless."

Perry chatters quietly.

Dean crouches down, too, and Perry can  _ feel _ how nervous he is. "Hey, buddy."

Perry walks away from Sam and over to Dean. Just like he did with Sam, he stays still, like the harmless little platypus he isn't.

"Good boy," Dean says nervously, slowly reaching a hand out. "Good boy."

Perry chatters. 

"You're not gonna kick me in the face again, are you?" Dean asks. 

Perry chatters again. 

Dean finally makes contact with Perry's back. Perry gives him a minute, just to convince the guy that he's safe, before turning around and biting his finger.

Dean yelps and pulls his hand away. "What was that for?"

"Bad Perry!" Phineas scolds him. 

Wow, this is shockingly similar to the first time Doofenshmirtz tried to open a portal into another dimension. 

"I'm sorry, Dean." Phineas scoops Perry up in his arms. "He's not usually like this. I don't know what's gotten into him."

"It's fine," Dean says. "Animals and I don't tend to get along."

"I'll go put him inside," Phineas says. 

Perry growls. He is  _ not _ going inside, especially if these two are staying out here. 

"Woah, buddy, what's wrong?" Phineas puts him back on the ground and sits in front of him with his legs crossed. "Are you okay, Perry?" 

Perry plops down and closes his eyes. He wants to look as innocent and peaceful as possible to avoid getting stuck in time out, but it's hard to stay awake with his eyes closed. He's a platypus, for goodness sake. He can't function with a human sleep pattern, and he's been up nonstop since seven o'clock this morning. He doesn't have much of a choice — he forces himself to open his eyes, just a little bit. 

"Is he okay?" Sam asks. 

"I think so," Phineas says. "I think he's just tired."

Perry chatters softly. Yes, yes he is. 

"I'll keep an eye on him," Sam offers. "You guys just get back to what you were doing."

"Thanks, Sam," Phineas says. "Usually, we would have given him to Isabella or Baljeet or Buford, but they had to go home. We're not usually out this late."

"Anything to help you help us," Sam says with a light-hearted smile. 

Phineas stands up and heads back to the table that Ferb has been using, and Sam takes his spot instead. Okay, new plan…

"Hey, bud," Sam says. "As much as I love watching Dean get his ass handed to him by a semi-aquatic monotreme, do you think you can leave him alone?"

"Dude!" Dean kicks him on the back. "You can't swear in front of children."

"Ooh, right," Sam mutters. "Sorry."

"It's okay," Phineas says. "I think they can bleep it out."

Dean stares at him. " _ Who _ can do  _ what _ ?" 

But Phineas is already back to work. 

Perry rolls onto his side and stares at the house. It's bright enough out that this forces him to keep his eyes open, but he needs to come up with a plan quickly, before he falls asleep. He can't just bite them. Phineas and Ferb don't understand that hint. He can't get anywhere near Dean if he doesn't want Phineas to drag him away. That leaves Sam, but what course of action could he take here? How does he get the message to the kids that these are bad people? 

_ He  _ figured it out when he saw them step through a portal with guns. That's got to work. He just needs to show Phineas and Ferb that they're armed. Perry rolls over and looks at Sam, trying to figure out the best way to do this. Unfortunately, he's not quite sure where the gun is, other than somewhere on his waist, so he has to scope it out. 

Perry curls up in Sam's lap, his tail against Sam's chest. He feels around with it, searching for any bumps he wouldn't find in Phineas or Ferb's laps. It takes a bit of subtle trial and error, but he does manage to find it. He jumps to his feet, turning around and digging his bill against Sam's waist. 

"Perry!" 

Phineas starts marching towards him, and Perry knows this is his last chance. Just as he feels the boy's hands around him, he grabs hold of the hilt of the gun in his teeth. Unfortunately, he also grabs Sam's shirt, so when Phineas pulls him a foot or so away, Perry has to let go if he wants to save his teeth. 

It must be his lucky day, because the gun falls to the ground anyway. Perry stops struggling and lets Phineas hold him with ease. The secret's out now. The kids know they're not safe. 

"Woah, what?" Phineas stumbles backwards. "You have a gun?"

"Yes?" Sam says uncertainly, bending down to pick it up. 

"This is a kids' show!" Phineas practically yells. "Why would you bring a gun to a kids' show?"

"We didn't come from a kids' show, and we weren't going to a kids' show," Dean says. "Where we were supposed to be going, we were going to need it."

"Oh." 

Phineas looks to Ferb, unsure how to feel about that. Ferb just shrugs. 

"Okay, Perry, you're going inside," Phineas says. "Let's go."

Perry wiggles around, trying to break free from Phineas's arms. Unfortunately, Phineas has held Perry hundreds of times, and he's not letting the platypus go that easily. They keep getting closer and closer to the door, and Perry is running out of options. So, with a heavy heart, he takes to his last resort. 

He turns around and bites Phineas on the lip. 

"Hey!" Phineas yelps, his grip loosening. 

Perry jumps down and runs as quickly as he can, before the guilt can get to him. He's not supposed to hurt his owners. He's supposed to protect them, and they're supposed to protect him. He knows this is for the best, but he'd much rather snuggle with the kid than bite him. 

"Perry, wait!" Phineas calls after him.

Perry hides behind the trashcan right before Phineas pokes his head out. 

"Perry, where are you?" Phineas yells. "Perry! Come back!"

Perry fights back a tear. Now Phineas is going to think this was his fault, and it wasn't. Not at all. If anything, it's Perry's fault. He's the one that accidentally let these two into the universe, and that's what started all of this. They could be curled up on the couch right now, but Perry  _ had _ to open an interdimensional portal in Danville. 

"He'll be back," Ferb says. "He always is."

Phineas sniffles. "But he bit me, Ferb. He's never done that before."

"He's just tired," Ferb says. 

"But what if he's mad at me?" Phineas asks. "What if he thinks I'm mad at him?"

"He'll be back," Ferb repeats firmly. 

"What if he doesn't come home by bedtime?" Phineas asks. "He's not supposed to sleep outside."

There's a pause, and Perry can only assume Ferb is doing something to comfort him. He's already said far more than he typically does in one day. Unfortunately, Perry can't see through a trash can, so he's not sure what's happening. 

"Okay, let's go try to fix the transistor," Phineas says. He sniffles one more time. "We'll send them home, and then we can look for Perry if he's not home yet."

Perry waits for the squeak of the closing gate's hinges before running off. Apparently he  _ does _ have to trust Doofenshmirtz with the lives of everyone in the tri-state area. This isn't going to end well.


	12. Chapter 12

"I don't get it," Doofenshmirtz says. "Why won't it do anything?"

"How would I know?" Vanessa asks, her hands on her hips. " _ You're _ the evil scientist, not me."

"You know, I bet Perry the Platypus would know how to fix it," Doofenshmirtz says. "He's smart that way. He knows how to  _ break _ any inator. I bet he could fix them, too."

"I don't think it works that way," Vanessa says. "All you have to do is smash it or unplug a wire or hit the self destruct button and it'll break."

"Yeah, well, you don't know Perry the Platypus like I do," Doofenshmirtz says, crossing his arms. 

Vanessa rolls her eyes. "Whatever."

There's a knock on the door, so Doofenshmirtz goes over to open it. It's no one he knows, though, so he's a little confused. "A platypus?"

The platypus pushes past him and heads straight for the inator blueprint closet. 

"Hey, you can't just barge in here and look through my blueprints!" Doofenshmirtz yells.

"Oh, Perry, you're back," Vanessa says. "Is everything okay?"

The platypus sticks a thumbs up out of the closet. 

"You know this platypus?" Doofenshmirtz says, confused. 

The platypus disappears into the closet, then, a moment later, Perry the Platypus steps out with his little fedora. 

"Oh, be careful, Perry the Platypus," Doofenshmirtz says. "Another platypus just broke in a few seconds ago."

Perry rolls his eyes and heads back into the closet. 

"What are you looking for?" Vanessa asks. "My dad already built the inator. It just doesn't work."

"I was actually hoping you would know how to fix it," Doofenshmirtz adds. 

Perry runs out of the closet and hands him a blueprint, panting slightly from whatever hurry he’s in. Doofenshmirtz takes it from him, and it's the blueprint to the platypus-translator-inator. 

"I thought you didn't like this," Doofenshmirtz says, confused. 

Perry clasps his hands and looks up at him, almost pleading. 

"Do you want me to make it?"

Perry nods. 

"Okay, as soon as I figure out this inator —"

Perry takes the blueprint and smacks Doofenshmirtz with it. 

"What was that for?" he asks, rubbing his arm. 

"I think he wants you to make it now," Vanessa says. 

"Don't you think the other-dimension-inator takes priority?" Doofenshmirtz asks. 

Perry shakes his head. 

"But why?" 

"Well, maybe if you  _ built it _ ," Vanessa says, "he could  _ tell you _ why this is so important."

"Good point," Doofenshmirtz agrees. "Okay, let's see. What do we need?" He takes the blueprint back and looks it over. "I think I have all this, actually." He needed to buy a couple parts for the other-dimension-inator, but when taking inventory to find the parts for that, he thinks he saw all the ones he would need for this inator.

As Doofenshmirtz scrambles to get all the parts for the new new inator — this is his third inator of the day; that has to be a new record — Perry paces back and forth by the overhang of the building. He has to admit, it's a little distracting, but Doofenshmirtz can tell that this is important to him, so he forces himself to stay focused. 

"Perry, calm down," Vanessa says, amused. "He's breaking apart old inators. You should be happy."

Perry just chatters, and not in a cheerful way. 

"It's going to be okay," Vanessa says. "It always is."

~~

"I'll be honest, Perry the Platypus," Doofenshmirtz says, holding up the platypus-translator-inator, "I don't know if this is going to work."

Perry holds it hands out anyway. 

"Okay, but if it doesn't work, don't get mad at me," Doofenshmirtz says. "I didn't have much to go on when I made it."

With that, Doofenshmirtz slips the platypus-translator-inator over Perry's head. It's a weird little helmet, with a bunch of pokey proddy thingies sticking out. He's sure they do something, but he doesn't remember making this blueprint, so he's not sure what it would be that they do.

"Say something," Doofenshmirtz says eagerly. 

Perry looks around uncertainly. "Um… hi?"

"It worked!" Doofenshmirtz jumps up and down, clapping his hands together. "I can talk to my nemesis now! I'm officially the only evil scientist in the whole tri-state area that can talk to my nemesis!"

"Congratulations," Perry says, and though it sounds incredibly deadpan and insincere, Doofenshmirtz chooses to think that’s just the way the platypus-translator-inator translated it. 

"There's so much I want to ask!" Doofenshmirtz says. "Like, what —"

"There's no time for that," Perry says. "We have to —" 

Doofenshmirtz stares at him, waiting for him to finish, but the platypus just stops. Doofenshmirtz looks at him, then at an equally confused Vanessa, then back at his nemesis. Nothing. 

"You good, Perry?" Vanessa asks. 

"It's just very hard to think with this voice talking for me," Perry says. He shakes his head as if clearing the thought from his mind. "Is there a transistor in the interdimensional-portal-inator?"

"Obviously," Doofenshmirtz says. "Otherwise it would blow the power throughout the entire tri-state area."

"Good," Perry says. "I need it."

What do you mean, you  _ need _ it?" Doofenshmirtz asks. "It's in the inator! You can't just take apart my inator! Not when we're so close to finishing it!'

"Someone else is making one just like this and —" Perry pauses. "This is very disorienting."

"Why would someone else be making an interdimensional-portal-inator?" Vanessa asks. 

"For the same reason we are," Perry says. "And I think all they need is a transistor."

"In that case, let's go bring them one," Doofenshmirtz says with a grin. He was really enjoying working with just his menesis and his daughter, but he wouldn't mind adding a few new friends to the mix. 

"I can do it," Perry says. 

"I know, but where's the fun in that?" Doofenshmirtz asks. 

"Well, um…" Perry clasps his hands in front of him and looks at the floor awkwardly.

"What?" Doofenshmirtz asks. "What is it?"

"I think he wants to do this alone," Vanessa says. 

"What? No, he doesn't," Doofenshmirtz says confidently. "I just built him a whole translating helmet! He wouldn't just leave after I built him a translating helmet!"

Perry looks between Doofenshmirtz and Vanessa for a moment, then gives a resigned sigh. "Let's go." 


	13. Chapter 13

Getting back to the Flynn-Fletcher house with the two Doofenshmirtzes is an experience, to say the least. Doofenshmirtz drives, obviously, and Vanessa sits shotgun. Perry would have been fine sitting in the back, but Doofenshmirtz refuses to let that happen, because a platypus can't wear a seatbelt and he wants to set a good example for Vanessa. Instead, he has Perry sit in Vanessa's lap, holding him as though she were the seatbelt. It's embarrassing, to say the least. 

"Doofenshmirtz?" Perry says warily. 

"What's up, platy-buddy?" Doofenshmirtz asks. 

"These people we're going to go see —"

"Are spies?" Doofenshmirtz guesses eagerly. "Or ninjas? Pirates?"

"They're normal," Perry says. "And they think I'm just a normal platypus. You  _ can't _ tell them that I'm not."

"Ooh, secrets!" Doofenshmirtz claps his hands, excited. "I love secrets!"

Perry just sighs. This is going to suck. Why did he let Doofenshmirtz guilt him into letting him come? 

They pull up on the street out front, and Perry finds out that Doofenshmirtz cannot parallel park to save his life. Perry takes the platypus-translator-inator off and sets it down between the front seats. He opens the door and hops off Vanessa's lap, and by the time he hits the ground, he's already hid his hat and he lands on all fours. 

Both Doofenshmirtzes get out, and Dr. Doofenshmirtz heads to the other side of the car. He looks around, puzzled. "Where did Perry the Platypus go?"

Perry chatters loudly. 

"He's right there," Vanessa says, pointing at him. 

"Not every platypus is Perry the Platypus, Vanessa," Doofenshmirtz says. "Perry the Platypus has a fedora."

"He's undercover, remember?" Vanessa says. "These people think he's just a normal platypus, so he —"

"So he left, and he put a normal platypus in his place!" Doofenshmirtz finishes for her. "Genius!"

"Dad —"

Perry taps Vanessa on the foot to get her attention and shakes his head. Perry could spell it out himself, and Doofenshmirtz still wouldn't get it. There's no point in trying to explain. 

"Okay, Dad, do you have the transistor?" Vanessa asks. 

Doofenshmirtz holds up the transistor. 

"Alright, let's go get this over with," she mutters, and Perry has to agree.

Perry leads them to the backyard, and Vanessa opens the gate for him. Perry expects them to be in and out, likely leaving Perry behind, but, obviously, that's too much to hope for. 

"Ferb?" Vanessa says in disbelief. 

Perry looks up at the boy, who smiles and waves without a word. How the heck does quiet little Ferb know Vanessa Doofenshmirtz?

"Hi, Vanessa!" Phineas says, also waving. "Hi, Vanessa's dad!"

"Hi, triangular-headed boy!" Doofenshmirtz replies. 

Phineas gasps. "Vanessa, you found Perry?" He runs over and picks his platypus up, giving him a hug. "Oh, Perry, I'm sorry, buddy! I didn't mean to scare you away!"

Perry chatters. 

"Wait,  _ you guys _ know Perry?" Vanessa says, shocked. 

"Yeah, he's our pet," Phineas says. "How do  _ you _ know Perry?"

"Oh, he, uh…" Vanessa looks at Perry nervously. "He comes by sometimes."

"Yeah, he's my nemesis," Doofenshmirtz adds. 

If Perry could slap him right now, he would.

"This platypus is your nemesis?" Sam repeats, amused. 

"No, not this one," Doofenshmirtz says. "This one's just a normal platypus. My nemesis is a suave, semi-aquatic personification of unstoppable dynamic fury. This platypus is just kinda… you know, a platypus. I don’t think it does much."

Phineas, Ferb, Sam, and Dean all stare at him. 

"He's joking," Vanessa says. "Perry can distract him sometimes, and his own poor planning messes everything up. Perry's just his scapegoat."

"No, he's not!" Doofenshmirtz says stubbornly. "He's —"

"Dad!" Vanessa glares at him. "Just give them the thingy!"

"Oh, right." Doofenshmirtz holds the transistor out to Phineas. "Perry the Platypus said you were looking for this."

"Perry said that?" Phineas repeats, confused. 

"A different Perry the Platypus," Doofenshmirtz replies. “Again, this platypus doesn’t do much.”

Phineas puts Perry down and takes the transistor. He looks it over for a moment. "I think this is just what we were looking for."

"So you can get us home?" Dean asks. 

"Only one way to find out," Phineas says. He joins Ferb at their work bench and hands his brother the transistor. "You can do the honors.”

Ferb adds the transistor to the portal opener that Perry can only assume is not called an other-dimension-inator. 

"Alright, Ferb!" Phineas says. "Power her up!"

Ferb does just that, and it opens a portal… 

… into the world that an evil Doofenshmirtz used to control. 

"Yeah, that's not our universe," Sam says. 

"It's not?" Phineas frowns. "I really wasn't really prepared for that."

Perry tugs on Doofenshmirtz's lab coat with his teeth before walking towards the gate. He'll explain the whole "loop of dimensions" thing, Doofenshmirtz can explain it to Phineas and Ferb, and they can somehow figure out where to go from there. 

"Bad Perry," Phineas scolds him. “Stop biting the pharmacist.”

“Actually, I’m not a pharmacist,” Doofenshmirtz says. “I’m a --”

Vanessa smacks him on the shoulder at the same time that Perry bites his leg, which shuts him up pretty quickly.

“Stop it!” Phineas picks the platypus up and tears him away from Doofenshmirtz's coat. "Come on, you're going to bed."

Perry growls. He can't just bite Phineas again. Even if Phineas did drop him, there's nowhere for him to go. He needs to stay out here. How does he convince Phineas of that, though? It’s not like the kid knows that Perry has more experience with interdimensional portals than anyone else here.

"I'll take him," Vanessa volunteers. 

"Thanks, but he'd probably just bite you," Phineas says. "I think he's tired."

"I'll be fine," Vanessa assures him. "I know Perry. He wouldn't bite me."

"I don't know; he bit me a few minutes ago," Phineas tells her. "He's never done that before."

"Just give her the platypus, for badness sake," Doofenshmirtz says, annoyed.

Phineas hesitates, then hands Perry over. He just chatters quietly. That seems to be all it takes to convince Phineas that he's calmed down, because he heads back to the portal. 

"You might want to keep him away from your face," Sam remarks. 

"Screw that," Dean says. "The thing could kick —"

"Stop saying you were attacked by a platypus," Sam interrupts. "It's embarrassing for both of us."

Vanessa whispers a quiet, "Were you trying to show us something?" in Perry's ear. 

Perry nods once, as subtly as he can. Vanessa puts him down, and he immediately heads for the gate. 

"Perry, you can't leave," Phineas says with a frown. 

"Why not?" Vanessa asks. "Doesn't he leave every day?"

"But not at night," Phineas says. "Platypuses aren't supposed to sleep outside."

"Ah, gotcha," Vanessa says. "I'll just follow him, make sure he doesn't get too far."

Perry trots over to Doofenshmirtz's car, where he waits for Vanessa to close the gate before standing up and putting on his fedora. He points at the platypus-translator-inator inside the car.

"Hang on," Vanessa says. She opens the door — Perry had wrongly assumed it was locked — and hands him the device, which Perry slips over his head. "And why'd you out the little hat on?" 

"Because your dad is an idiot and Major Monogram has drilled the dress code into my head since birth," Perry says simply.

"Fair point," she says. "What do you need?"

"I need you to explain to Phineas and Ferb how dimensions work," Perry says. 

Vanessa stares at him blankly. "Okay?"

Perry explains the cycle of dimensions, and how you can only go forward unless you generate a very large amount of power, in which case you can go backwards once. Unfortunately, given that they have no idea where Sam and Dean’s universe is, it’s not as simple as going forward or backwards. He also adds that if worse comes to worse, they can just give Sam and Dean the remote to keep opening portals, because as long as they're out of this dimension, Perry doesn't particularly care where they are. 

"How do you know all that?" Vanessa asks. 

Perry pauses. Vanessa wasn't involved in this alternate universe, so Monogram never specifically forbade her from knowing about it. He hadn't exactly expected Perry to learn to communicate, after all. It would certainly be easier to explain it than it would be to make up an excuse. 

Unfortunately, he's decently sure he would be in very, very deep trouble if Monogram found out that he told her, so Perry just tosses the platypus-translator-inator in the car, takes off his fedora, and plops back on the ground with a mindless chatter. 

Vanessa laughs quietly to herself. "Okay, Perry. Let's go."

Vanessa picks Perry up, and they head back to the yard, where a very confused group of people are still trying to figure this out. Vanessa puts Perry back down, and he curls up by her feet and closes his eyes. If something goes wrong, he'll hear it. If not, he'll take whatever rest he can get. He has to be up early tomorrow to fight Doofenshmirtz, and he needs at least a little sleep.

He only half listens as Vanessa repeats what Perry told her, prefaced by a “what if” so no one gets suspicious. Phineas seems to think she may have a point, but now they have to figure out what to do with that information. It was easy last time, when all they had to do was go back a dimension -- though they did end up going forward a bunch of dimensions anyway, which was not fun -- but they have no idea how to get to Sam and Dean’s dimension. It’s not like they can map out every single dimension. 

“Can I go get Mom yet?” 

Perry looks up at the sound of Candace’s voice. She’s already in her pajamas, one hand on the door handle and one hand holding Mr. Miggins. She freezes when she sees everyone out there, though whether she’s upset that Phineas and Ferb seem to be throwing a mini party, embarrassed that everyone can see her in her pajamas, or just amazed at the giant contraption in the backyard, Perry isn’t quite sure. 

“Vanessa?” Candace gapes at her, her jaw practically on the floor.

“Oh, hi, Candace,” Vanessa says, like it’s completely normal to run into this girl with whom she has nothing in common, while she’s standing in the backyard with her little brothers. Perry just wants to know how these two know each other. 

“What are you doing here?” Candace asks. 

“I think I’m helping your brothers open a portal into another dimension,” Vanessa replies.

“Why are you  _ helping  _ them?” Candace asks.

“My dad had the part they needed,” Vanessa says with a shrug. Fortunately, Danville is just weird enough that no one questions how the Doofenshmirtzes knew they needed it.

“So, what, you guys are done now?” Candace asks her brothers. “You’re gonna send them away and the whole thing will disappear by the time I get Mom?”

“Not quite,” Phineas says, before explaining the whole thing about dimensions being a loop that has already been explained a million times and doesn’t bear repeating. “So, until we figure out how to get them to the right dimension, they’re stuck here.”

“I don’t get it,” Candace says. “Why don’t you just keep opening up portals until it’s the right one?”

“Because we don’t know how many dimensions they would have to go through,” Phineas says. 

“So? Just keep shooting portals inside of portals inside of portals,” Candace says. “You gotta get there eventually.”

Everyone pauses. She’s not wrong. She may have no idea what she’s talking about, but she’s still not wrong.

“Should we?” Phineas asks.

Ferb pushes the button, and, after a big show of lights, a second portal opens up inside the first portal. He looks at Sam and Dean expectantly.

“Not that one,” Sam says. 

Ferb presses the button again, and another portal opens.

“Not that one, either,” Dean says.  So Ferb presses the button, and it’s not that one, so he presses it again, and it’s not that one, so he presses it again and it’s not that one, so he…

Perry closes his eyes again. He’s not going to sleep, but a little rest is better than none. He still gets to listen as Sam and Dean tell everyone that they’re not looking at their universe, and he gets to listen to the reactions of people looking through all these weird universes for what they think is the first time. It’s probably a lot cooler looking at them when you’re not being chased by evil robots. 

And then Perry falls asleep, because he’s not as good at staying focused as he thought he was.


	14. Chapter 14

“I think that’s it,” Dean says. “But that’s what we’ve said about, like, 20 other universes, so we’ll see, I guess.”

“Go ahead, check it out,” Phineas says. “We’ll be here if it isn’t.”

So Sam and Dean head through the long line of portals that only takes a single step. These portals are so close together, they might as well be occupying the same space. 

Dean looks around. It's hard to tell whether they're home. Sure, everything finally looks like it's in the right color pallet, but that doesn't mean too much. There's only one way to find out. Dean pulls out his cellphone, which is just about dead after all this. 

"Dude!" Dean smacks Sam on the shoulder excitedly. "I've got a signal!"

"Call Cas," Sam says quickly. "See if this is our world."

So that's what he does. He’s been anxious about speaking to the angle before, usually after something relationship-shattering occurs, but now he’s anxious for a whole different reason. He knows Castiel won’t be mad at him, which is a rare occurrence because they always seem to be fighting about something, but what if this isn’t his dimension? What if this phone number belongs to someone else? What if it belongs to a Castiel who knows a different set of Winchesters? So much could go wrong. 

"Dean?"

He breathes a sigh of relief when he hears that voice coming through the speaker. "Cas, thank god."

"Dean, where are you?" Castiel asks. “I’ve been trying to call you for hours.”

"I don't know," Dean admits. The best he's got is  _ outside _ .

"Cas, what was the last you heard from us?” Sam asks. 

"Just that you were looking for Jack,” Castiel says. “I tried calling you for an update, and you wouldn’t answer.”

"We did it," Dean says, amazed. "We made it back."

"I can't believe it," Sam says. 

"What is happening right now?" Castiel asks. 

"We gotta go," Dean says. "Cas, buddy, I've never been so relieved to hear your voice."

"What?"

"See you in a few," Dean says before hanging up. He only has so much battery left, and he's not wasting it all now. They may have found the right universe, but they still have to get home. 

"Do you want to go back and ask if we can have the blueprints?" Sam asks. "We can go find Jack and Mom and Kaia…”

"We might as well," Dean says. “It would have been a hell of a lot easier to have Jack pull Mom back, but this is just about the easiest Plan B we’ve ever had.”

“Alright, let’s go.”

They step back through the portals, where everyone is still waiting anxiously to see if it worked. When they come back, everyone deflates, obviously expecting this to be the wrong universe.

"Thanks, Phineas," Sam says. "You did it."

"You made it home?" Phineas beams. "That's awesome!"

"Do you think we can take the blueprints with us?" Dean asks. "We still have a different alternate dimension to get to."

“Maybe a few of ‘em,” Sam adds. They have no idea where Jack and Kaia would have ended up.

"Wanna just take the whole machine?" Phineas asks. 

"Can we do that?" Sam asks. 

Phineas looks to Ferb as if waiting for an objection, but Ferb just shrugs, so Phineas says, "Yeah, sure. We still have a lot to do in this dimension before we move on to a different one, anyway."

Sam chuckles. "Thanks, kid. We owe you one."

"No way," Phineas says. "This is one of the coolest things that's ever happened to us."

"It says a lot about you guys that this is only  _ one of _ the coolest," Dean remarks. "Alright, take care, guys. Never stop building."

"Don't worry, we won't," Phineas says. "There's 104 days of summer vacation, and we're gonna make the most of every one."

"Though it does feel like it's been a lot longer than 104 days," Ferb says. 

"Yes, yes it does," Phineas agrees. 

"See ya later," Dean says. "Except, you know, hopefully we won’t have to."

Sam and Dean both take hold of one side of the machine, and together, they pull both the portal maker and the remote through the portals and into their dimension. They turn back around and wave through the dimensional gateway, and everyone crowds in and waves back. With the press of a button, the portal closes, and they’re tucked safely back in their dimension. 

"Wait a second," Dean says. 

"What?" Sam asks. 

"I know that store," Dean says. "That's, like, a two minutes drive from the bunker."

Sam looks around. "You're right. We're practically home already."

"Well, let's go," Dean says. "We gotta get this thing home. They’re still out there somewhere."

"Not for long," Sam says, and for the first time in a long time, there's hope. 


	15. Chapter 15

Vanessa nudges Perry with her foot. "Wake up, sleepyhead."

Perry makes a small, annoyed noise and shifts a little, but he doesn't wake up. 

"Hey, Perry." She nudges him again.

Perry doesn't even move.

"What do you know? He really  _ was  _ tired," Phineas remarks. "Well, that was fun, but I think Perry's right. It's getting late."

"I can't believe the sun's about to go down, and Mom hasn't come out to check on you  _ once _ ," Candace mutters. "You are so lucky they took that thing with you, or you would have been so busted."

"Thanks for the transistor, Vanessa and Mr. Doofenshmirtz," Phineas says. "We couldn't have done this without you."

"No problem," Vanessa says. 

"And it's  _ Dr _ . Doofenshmirtz," he adds. 

"You're not a doctor for buying a 15 dollar certificate online, Dad," Vanessa says, rolling her eyes. "We're gonna head home now. Bye, Ferb."

Ferb waves. 

Vanessa crouches next to the platypus. "Perry, you gonna wake up so I can say goodbye?"

Perry doesn't move.

"I got him," Phineas says. He scoops Perry up in his arms, and the platypus makes a content noise. "Hey, buddy, wake up."

Perry slowly opens his eyes, awkwardly squinting and not really awake. 

"You missed all the fun," Phineas says. "Sam and Dean already went home."

Perry closes his eyes again. 

"Vanessa, hurry up!" Doofenshmirtz whines. 

That wakes Perry up immediately, and he jumps out of Phineas's arms. He looks around, but after a moment, he seems to remember what's happening and why Doofenshmirtz is here because he calms down. 

"Hey, Perry," Vanessa says. "Don't be a stranger. See you tomorrow?"

Perry just chatters. 

"I will take that as a yes," Vanessa says. 

Vanessa and Doofenshmirtz head out, and Phineas, Ferb, and Candace all head inside. Phineas looks back before closing the door, and he just barely catches Perry's tail disappearing through the gate as he's walking out of the yard. 

"Should we go follow him?" Phineas asks. 

Ferb just shrugs. 

"Alright, we can wait," Phineas says. "I have to admit, today might have been the weirdest day of summer yet."

"Every day is the weirdest day of summer for you," Candace remarks. 

"I guess you're right," Phineas says. "We  _ did  _ steal a mummy once."

"I defeated a robotic Minotaur," Candace says. " _ That's _ the weirdest one for me."

"How about you, Ferb?" Phineas asks. 

"I think every day is a new weird, and it would be pointless to compare."

Phineas nods. "I couldn't have said it better myself."

~~

Perry follows the Doofenshmirtzes to their car, but no one seems to notice him until he stands up, puts his hat back on, and chatters. 

"Oh, hey, Perry," Vanessa says. "What's up?"

Perry points to the car. 

"What?" Doofenshmirtz asks. "Do you need a ride? I don't get it."

Vanessa rolls her eyes and pulls out the platypus-translator-inator. She hands it to him, and he puts it on over his fedora, once again rendering the hat useless. 

"I just want to thank you," Perry says. "You know, before the truce is broken and I go back to thwarting your evil plans."

"Oh, no problem, Perry the Platypus," Doofenshmirtz says. "But where did you go? I thought you were going to come with us."

Perry just sighs. What an idiot. 

"So, I was thinking," Doofenshmirtz says, "since I basically built three inators today, I'm two days ahead of schedule. Maybe, instead of you breaking down my door or my wall or my ceiling and destroying my inator tomorrow, do you want to just get a coffee?"

Perry stares at him.

"You know, make use of the platypus-translator-inator," Doofenshmirtz says. "There's so much I want to know."

"You mean extend the peace treaty for a day?" Perry says warily. There's definitely a lot he would like to tell the guy, but, again, he  _ can't _ . OWCA has rules for a reason.

"Yeah, why not?" Doofenshmirtz says with a shrug. "Think of all the money I'll save if you just walk through the front door like a normal platypus."

Perry frowns. "I don't think…" 

He doesn't want to say no. He really would like to just hang out. They've done it before, from tea breaks during a platypus fight to tanning in his suburban house's lawn, and it was always fairly enjoyable before they inevitably started fighting again. But Monogram would never let that slide.

"Is that a no?" Doofenshmirtz asks. 

Perry hesitates before nodding solemnly. "I'm sorry. I'd get in a lot of trouble."

"Why should Monogram have to know?" Vanessa asks. "It wouldn't be the first secret you've kept from him."

She does have a point. If Monogram found out that Perry knew Monty was consorting with the enemy, he'd probably get fired. If he's managed to keep that from him for so long, he can probably get away with  _ one day _ of talking to Doofenshmirtz. 

"If this is just about Francis, I can explode my own inator," Doofenshmirtz says. “It would be a great way to use up some old parts.”

"Fine," Perry concedes. "I'll see you tomorrow." He takes the helmet off, hands it to Doofenshmirtz, and then he's off to the backyard. 

"I like him," Vanessa remarks. 

"Me, too," Doofenshmirtz replies. "You know, I bet Peter the Panda wouldn't spend a day having coffee and talking to me."

"Who's Peter the Panda?" Vanessa asks. 

"Oh, he's my old nemesis," Doofenshmirtz says. "You know, for a few days, 'til I realized I liked Perry the Platypus more."

"Well, I'm glad you did," she says. "I can't imagine my dad having a cooler nemesis."

~~

Sam and Dean have to lug the whole portal machine to the bunker, which, needless to say, is not easy. What should have been a 10-minute walk ends up taking almost a full half hour, but eventually, they manage to make their way back. 

Castiel is sitting anxiously at the table in the war room. As soon as the door opens, he stands up, ready to greet them and make sure they're okay. He's been calling them for hours, only to find out that they were in another dimension. He needs to know they're okay. 

Sam and Dean push the portal machine into the bunker, leaving it at the top of the stairs before heading down to see their friend. 

"Cas, buddy, hey," Dean says with a grin. 

"What is that?" Castiel asked, suddenly much more interested in this giant hunk of metal than the Winchesters. 

"It opens portals into other dimensions," Sam says. "It's a long story. Have you heard from Jack?"

"No, I thought he was with you," Castiel says, confused. "How did you get to another dimension without Jack?"

"Well, we  _ had _ Jack," Dean says. "He threw us through a portal, and we all got separated."

"But if it worked for him like it did for us, he's fine," Sam adds. "We landed a few blocks from some kids who built this whole thing in a few hours."

"And they had a teal platypus that could  _ really  _ fight," Dean adds. "I mean, seriously, the thing could take  _ you _ down."

Sam rolls his eyes. "No one's buying your platypus story."

"I swear to god, Sam, that platypus kicked me in the face," Dean says. 

"Did you say the platypus was teal?" Castiel asks, his head cocked to the side. 

"Yeah, it was a weird dimension," Sam says. 

"But you're okay?" Castiel asks. "Both of you?"

"Never better," Dean says. He pats the portal-opening machine. "Now come on. We got some friends to find." 


End file.
